The last several years have witnessed an explosion in our understanding of vertebrate development, largely based on work from a few model genetic organisms. The zebrafish is the newest of these model organisms. Because the basic principles of body patterning appear similarly during embryogenesis of all vertebrates, insights gained from work on embryonic zebrafish will have implications for human health and disease. Moreover, research on this organism meets the intent of the Animal Welfare Act because use of many higher vertebrates can now be replaced by use of this lower vertebrate. Systematic genetic research on zebrafish began at the University of Oregon and for many years Eugene was the only place it was performed. Recently, however, international interest in this organism has grown tremendously; studies of the embryology and genetics of zebrafish and the recent identification of over 7,000 genetic mutations have led to a dramatic increased in the number of laboratories using this organism to study the basic mechanisms of vertebrate development. Currently these genetic stocks are distributed among more than 100 laboratories in 28 countries. To make room for new mutants, laboratories must discontinue some of their current stocks many of which are permanently lost. The zebrafish research community desperately needs a centralized site to preserve and keep track of these stocks and facilitate their distribution to researchers, thus supporting and promoting research opportunities whole preventing duplication of effort. We propose to construct a facility to maintain wild-type and mutant stocks of zebrafish and to make these stocks widely available to the international research community. A stock center is needed because it can eliminate the requirement of individual laboratories to maintain stocks they are unable to study, it can provide animals at lower cost than individual laboratories, and most importantly, it can ensure the higher possible levels of quality and uniformity. Specifically we propose: 1. To establish a stock center to serve as a central repository for materials and information. 2. To make information widely available to the research community. 3. To develop methods for improving health.